Small Engines (Lawn Mowers, etc.): oil in gas tank, first tank, gas tank

Question
My son accidentally put oil in the gas tank of my brand new MTD  21" rear discharge push lawnmower (410 series). I drained the oil out of the gas tank the best I could. Do I need to have the gas tank professionally cleaned out?

Thanks!

Answer
If you drained as much as you could out, make sure you also drain the carburetor float bowl.  Then fill with fresh gasoline.  The gasoline will mix with the oil and clean the tank for you...it might smoke for the first tank but it will be fine.  Hope this helps.